Dr. Cesar Victora is a world-renowned Brazilian researcher who led the recently published 30-year Brazilian breastfeeding study. He spoke with UNICEF about his research findings and the association between breastfeeding duration with higher performance in intelligence tests, education attainment, and income at age 30. Below is a synthesis of our conversation with him on 9 July 2015.

We know that breastfeeding protects against disease and death, but your study found that there were educational and economic benefits?
Breastfeeding may have long-term consequences not only for the child’s health but for the mother’s health as well. I think there is a general mistake that breastfeeding is only important in poor countries because much of the early research on breastfeeding was on its role in reducing pneumonia, diarrhea, and other infections. It is a mistake to think that breastfeeding is not important in high- or middle-income societies.

Breastfeeding is one of the care interventions that programmes an individual for being healthier later in life. We have evidence that breastfeeding may prevent obesity later in life and it also reduced the risk of Type 2 diabetes. We are just scratching the surface regarding two biological mechanisms that may explain these connections.

First, there may be a gene that is switched on by exposure to breastmilk in the early stage of life. The second is that the characteristics of the microbiome in a person’s gut are programmed for life by early exposure to foods and other environmental bacteria. So children who are breastfed may be protected against conditions such as obesity because of their different microbiome.

For the mother, we have evidence that women who breastfeed longer are less likely to develop breast cancer, which is the number one cause of cancer death in women. It also protects against ovarian cancer.

We’re just now realizing the importance or breastfeeding. Breastfeeding has a definite impact on IQ. Our study published in April in The Lancet demonstrated that children who were breastfed longer were not only more intelligent but once they were adults they had more schooling and their salaries were substantially higher than similar individuals who were not breastfed as children.

How do you see this information shaping policy makers decisions regarding breastfeeding and then parent’s decisions regarding breastfeeding?
I think breastfeeding is not just a matter of health; it’s a matter of human capital. By investing in breastfeeding we will have healthier, stronger and more productive adults in the next generation. It’s a long-term investment. Allocating resources to breastfeeding promotion and moving mothers toward breastfeeding will have a long-term economic benefits for the country.

Our paper in April got a huge coverage in the media, a lot of positive coverage but we also had some negative covers – mainly mothers saying “Oh, you’re making mothers feel guilty! This is not fair.” A study that shows that breastfeeding is great for mothers and children isn’t a critique of women.

This not a personal issue. This is a societal issue. Society has to be breastfeeding friendly. By that I mean having the right policies in place about maternity leave and being able to have a nursery in the work place so women can breastfeed [or] express breast milk during work hours. Brazil has implemented fines for anyone who tells a mother not to breastfeed in a public place.

You mentioned people are fined for criticizing a woman breastfeeding in public. What about the policies for private and public employers on breastfeeding in the work place?
[In Brazil] maternity leave is not just about breastfeeding. It is also about being around to help the child in many different ways. We have four months mostly paid maternity leave in Brazil that [we are trying to] extend to six months. There was a strong movement here and there [are] lots of members of Parliament interested in pushing for [six months leave]. I think it will go through and be successful.

That’s the sort of thing that needs to be done everywhere. Fathers now get a week. The hope is that they will get at least a couple of weeks to stay home with pay.

Maternity leave should be part of society’s role – it should be society’s responsibility and it should not be economically penalizing those mothers who cannot afford to be without pay for over a month.

Even with six months of maternity leave, your studies showed nursing for additional six months bumped up benefits even further. Is there anything you’ve seen that stands in the way of the benefits of that extended breastfeeding?
I think it’s important to recognize that the current recommendation by the World Health Organization and UNICEF [is] exclusive breastfeeding up to six months. We need a policy that will allow a woman to breastfeed exclusively during the first six months. That’s why the maternity leave is so important.

After the first six months we know that the child will need more types of food. We do not recommend that they receive other types of milk but they can definitely receive some fruits, vegetables, meat, and so on. That means the mother doesn’t have to be with the child for 24 hours a day but she does need either a day-care centre close to where she works or we need other arrangements for the mother to breastfeed.

In Brazil there has been societal change. When I started studying in the 1980s, the total duration of breastfeeding – any breastfeeding, not just exclusive breastfeeding – was three months. Now the median duration is fourteen months. Having changed the median duration from three to over fourteen months in one generation is remarkable. Thirty years ago it was only 10-20% that would breastfeed at all up to a year. It’s a huge change.

Do you have any final remarks?
Breastfeeding is important for rich and poor individuals alike and for rich countries and poor countries. Not only for the short term benefits to the child but for the long-term benefits for the child, the mother, the economy and the environment too.